Line of credit net of letters of credit outstanding.

No definition available.

Name:	apg_LineOfCreditNetOfLettersOfCreditOutstanding
Namespace Prefix:	apg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Unswapped portion of line of credit.

+ References

No definition available.

+ Details

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Namespace Prefix:	apg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-1A

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The effective interest rate during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

+ Details

Name:	us-gaap_NotesPayable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

+ Details

Name:	us-gaap_SecuredDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ShortTermDebtLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Balance Type:
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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
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Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=apg_TwoThousandNineteenTermLoanMember
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- Details

Name:	us-gaap_DebtInstrumentAxis=apg_TermLoanFacilityMember
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Balance Type:
Period Type:

- Details

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- Details

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DEBT - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
DEBT - Additional Information (Detail) - USD ($)	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2021	Feb. 28, 2024
Short-term Debt [Line Items]
Line of credit, maximum borrowing capacity				$ 300,000,000
Derivative notional amount	$ 2,320,000,000	$ 2,264,000,000
Acquisition of Construction Equipment and Vehicles
Short-term Debt [Line Items]
Notes payable	5,000,000	5,000,000
Interest rate swaps
Short-term Debt [Line Items]
Derivative notional amount	$ 1,120,000,000
Derivative, fixed interest rate	3.52%
2019 Term Loan
Short-term Debt [Line Items]
Line of credit outstanding	$ 330,000,000
2021 Term Loan
Short-term Debt [Line Items]
Line of credit outstanding	1,707,000,000
Term loan facility \| 2019 Term Loan
Short-term Debt [Line Items]
Secured term loan	1,200,000,000
Remaining line of credit outstanding (unswapped portion)	$ 917,000,000
Term loan facility \| 2019 Term Loan \| Interest rate swaps
Short-term Debt [Line Items]
Derivative, fixed interest rate	3.59%
Term loan facility \| 2019 Term Loan \| Base Rate
Short-term Debt [Line Items]
Debt, variable interest rate	1.25%
Term loan facility \| 2019 Term Loan \| Eurodollar
Short-term Debt [Line Items]
Debt, variable interest rate	2.25%
Term loan facility \| 2019 Term Loan \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Interest rate swaps
Short-term Debt [Line Items]
Derivative notional amount	$ 720,000,000
Derivative, fixed interest rate	3.59%
Term loan facility \| 2019 Term Loan \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Interest rate swaps \| Minimum
Short-term Debt [Line Items]
Term loan interest, basis points	2.25%
Term loan facility \| 2019 Term Loan \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Interest rate swaps \| Maximum
Short-term Debt [Line Items]
Term loan interest, basis points	2.50%
Term loan facility \| 2021 Term Loan
Short-term Debt [Line Items]
Line of credit, maximum borrowing capacity	$ 300,000,000
Term loan facility \| 2021 Term Loan \| Base Rate
Short-term Debt [Line Items]
Debt, variable interest rate	1.50%
Term loan facility \| 2021 Term Loan \| Eurodollar
Short-term Debt [Line Items]
Debt, variable interest rate	2.50%
Term loan facility \| 2021 Term Loan \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Interest rate swaps
Short-term Debt [Line Items]
Derivative notional amount	$ 400,000,000
Derivative, fixed interest rate	3.41%
Term loan facility \| Revolving Credit Facility
Short-term Debt [Line Items]
Line of credit outstanding	$ 100,000,000	0
Secured term loan	$ 500,000,000
Debt instrument term	5 years
Line of credit net letters of credit outstanding	$ 396,000,000	495,000,000
Letters of credit outstanding	$ 4,000,000	$ 5,000,000
Term loan facility \| Revolving Credit Facility \| Base Rate
Short-term Debt [Line Items]
Debt, variable interest rate	1.25%
Term loan facility \| Revolving Credit Facility \| Eurodollar
Short-term Debt [Line Items]
Debt, variable interest rate	2.25%
$4.125% Senior Notes
Short-term Debt [Line Items]
Repurchase amount of senior notes	$ 337,000,000
$4.125% Senior Notes \| APi Group DE, Inc
Short-term Debt [Line Items]
Line of credit outstanding			$ 350,000,000
Line of credit facility, interest rate	4.125%	4.125%	4.125%
$4.750% Senior Notes
Short-term Debt [Line Items]
Repurchase amount of senior notes	$ 277,000,000
$4.750% Senior Notes \| APi Group DE, Inc
Short-term Debt [Line Items]
Line of credit outstanding			$ 300,000,000
Line of credit facility, interest rate	4.75%	4.75%	4.75%